The goal of this SBIR R&D program is to commercialize a diagnostic spectrofluorimeter (DSF) for use by gastroenterologists performing endoscopic surveillance for colorectal dysplasia/carcinoma. The DSF will consist of a compact, special purpose spectrofluorimeter and a specially designed optical fiber diagnostic probe. The probe is passed through the biopsy channel of a standard colonoscope and brought into contact with the colonic mucosa. The DSF will excite, collect and analyze mucosal autofluorescence to indicate the presence of dysplasia. It will guide biopsy and enable real-time spectroscopic assessment of tissue suspected of being dysplastic. The objective of Phase l is to develop the prototype design of this unit. The specific aims are to accomplish (l) subsystem optimization, (2) system optimization and (3) prototype design of an integrated, compact, easy-to-use prototype unit which would be constructed and clinically tested in a Phase II effort. The program will employ background knowledge and technology developed at MIT under NIH support. Innovation in this project will come in areas of system optimization and engineering design.